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Operating partnership redemption units for cash.

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Stockholders equity note.

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Date the declared dividend will be paid, in CCYY-MM-DD format.

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The per share amount of a dividend declared, but not paid, as of the financial reporting date.

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Date the dividend to be paid was declared, in CCYY-MM-DD format.

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Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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Total change in each class of partners' capital accounts during the year due to redemptions and adjustments to redemption value. All partners include general, limited and preferred partners.

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The number of units redeemed during the year of each class of partners' capital account. Units represent shares of ownership of the general, limited, and preferred partners.

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Number of new stock issued during the period.

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Amount of stock repurchase plan authorized.

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Amount remaining of a stock repurchase plan authorized.

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Number of shares that have been repurchased and retired during the period.

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Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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Stockholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Thousands			1 Months Ended		3 Months Ended
	Apr. 28, 2021	Mar. 15, 2021	May 03, 2021	Mar. 31, 2021	Mar. 31, 2021	Mar. 31, 2020	Feb. 29, 2020	May 31, 2018
Stockholders Equity Note [Line Items]
Cash proceeds for redemption					$ 50,828,000
Common stock repurchases, value					119,269,000	$ 353,720,000
Common Stock [Member]
Stockholders Equity Note [Line Items]
Cash proceeds for redemption					$ 0
Common stock repurchases, Shares					3,150	10,861
Common stock repurchases, value					$ 31,000	$ 109,000
Share Repurchase Program [Member] \| Common Stock [Member]
Stockholders Equity Note [Line Items]
Authorized amount of stock repurchase								$ 2,000,000,000.0
Share Repurchase Program Two [Member] \| Common Stock [Member]
Stockholders Equity Note [Line Items]
Authorized amount of stock repurchase							$ 3,000,000,000.0
Repurchase of common stock, remaining amount				$ 2,900,000,000	$ 2,900,000,000
Share Repurchase Program [Member] \| Common Stock [Member]
Stockholders Equity Note [Line Items]
Common stock repurchases, Shares					3,000	11,000
Stock repurchased, average price per share					$ 37.87	$ 32.57
Common stock repurchases, value					$ 119,000,000	$ 354,000,000
Subsequent Event [Member]
Stockholders Equity Note [Line Items]
Dividend declared date	Apr. 28, 2021
Dividends declared per share	$ 0.0025
Dividend paid date	Jun. 15, 2021
Dividend record date	Jun. 10, 2021
Subsequent Event [Member] \| Share Repurchase Program [Member] \| Common Stock [Member]
Stockholders Equity Note [Line Items]
Common stock repurchases, Shares			1,000
Stock repurchased, average price per share			$ 39.10
Common stock repurchases, value			$ 56,000,000
MGM Growth Properties LLC [Member] \| Operating Partnership [Member]
Stockholders Equity Note [Line Items]
Partnership interest		42.10%		42.10%	42.10%
Operating partnership units, redeemed				37,000
Operating partnership units, redeemed for cash				15,000
Operating partnership units, redeemed for Class A offering				22,000
Cash proceeds for redemption				$ 1,200,000,000
MGM Growth Properties LLC [Member] \| Class A shares [Member]
Stockholders Equity Note [Line Items]
New issuance of shares		22,000